Check valves are valves that allow fluid flow in one direction therethrough and prevent flow in the opposite direction. They are widely used in a range of applications, for example in air conditioning systems, for example in aircraft air conditioning systems.
Check valves commonly include a pair of valve elements or flappers located at an opening in a valve housing. The flappers are hingedly supported on a hinge pin which extends between mounting posts arranged on the valve housing on opposite sides of the valve opening for rotation between a closed position in which they lie across and close the opening, preventing fluid flow through the opening in one direction and an open position in which, under the pressure of a fluid (gas or liquid) on one side of the check valve, the flappers rotate from their closed positions so as to allow the fluid to flow through the valve in the opposite direction.
The hinge pin must be mounted to the valve housing securely. Typically, a securing element such as a retaining ring is mounted to the housing. However, there remains the risk that such elements may loosen or even detach, leading to improper operation or even failure of the valve.
The present disclosure relates to a check valve which includes a modified hinge pin arrangement.